XIV] SELAGINELLITES 85 



Selaginellites. 



This generic name has been instituted by Zeiller^ for 

 specimens from the coal basis of Blanzy (France). It is applied 

 to heterosporous species with the habit of Selaginella: Zeiller 

 preferred the designation Selaginellites to Selaginella on the 

 ground that the type species differs from recent forms in having 

 more than four megaspores in each megasporangium. It is, 

 however, convenient to extend the term to all heterosporous 

 fossil species irrespective of the spore-output. 



Selaginellites Suissei Zeiller. 



This species was described in Zeiller's preliminary note^ as 

 Lycopodites Suissei, but he afterwards transferred it to the genus 

 Selaginellites. In habit the plant bears a close resemblance to 

 Lycopodites macrophyllus of Goldenberg ; the shoots, 1 — 3 mm. 

 thick, are branched in a more or less dichotomous fashion and 

 bear tetrastichous leaves. The larger leaves reach a length of 

 4 — 6 mm. and a breadth of 2 — 3 mm ; the smaller leaves are 

 described as almost invisible, closely applied to the axis, oval- 

 lanceolate and 1 — 2 mm. long with a breadth of 0"5 — 075 mm. 

 Long and narrow strobili (15 cm. by 8 — 10 mm.) terminate the 

 fertile branches ; these bear crowded sporophylls with a trian- 

 gular lamina and finely denticulate margin. Oval sporangia 

 were found on the lower sporophylls containing 16 — 24 spherical 

 megaspores 0-6 — 0"65 mm. in diameter. The outer membrane 

 of the spore is characterised by fine anastomosing ridges and 

 thin plates radiating from the apex and forming an equatorial 

 collarette. The microspores have a diameter of 40 — 60/t and 

 the same type of outer membrane as in the megaspores. The 

 megaspores of the recent species Selaginella caulescens, as 

 figured by Bennie and Kidston^ resemble those of the Palaeozoic 

 type in the presence of an equatorial flange. It is interesting 

 to find that, in spite of the occurrence of 16—24 megaspores 

 in a single sporangium the size of the fossil spores exceeds 

 that of the recent species. 



1 Zeiller (06) p. 141, Pis. xxxix. xli. ^ Zeiller (00) p. 1077. 



3 Bennie and Kidston (88) PI. vi. flg. 22. 



